Petition By-elections to be called automatically when MPs defect to another party
When an MP decides they want to defect to another party a by-election should be automatically triggered to allow the constituents the opportunity have their democratic right to agree or not with their elected official.
More details
Regardless of political views I believe you vote for both the individual candidates and their stance on issues and the more general direction and policies of the party they stand for. When an MP decides that they no longer wish to be a member of the party they stood for when you voted for them the electorate should have the opportunity to also change their mind by voting in a by-election.
128,790 signatures
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100,000 signatures required to be considered for a debate in Parliament
Parliament will debate this petition
Parliament will debate this petition on 16 March 2026.
You'll be able to watch online on the UK Parliament YouTube channel.
Government responded
This response was given on 9 February 2026
There are no plans to make changes to the current constitutional arrangements, whereby voters elect individual candidates, and not the political party they represent.
Read the response in full
It is an established constitutional principle that at UK General Elections, voters cast their vote for individual candidates, and not the political party they represent.
When a Member of Parliament (MP) decides to change their party affiliation, it is for the MP to decide whether to continue to sit in the House of Commons (as a representative of their new political party or as an independent MP) or to stand down from their seat to trigger a by-election and, if they wish, seek re-election.
There are no plans to make changes to the current arrangements.
Cabinet Office